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0825692794dinh
2 năm trước
Từ mặt đất người ta ném thẳng đứng một vật lên cao với vân tốc ban đầu v=20m/s . Tính độ cao tối đa mà vật đạt được . Lấy g=10m/s2
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Look at the sentences below about Tanya Streeter, a professional diver. Read the text on the opposite page to decide if each sentence is correct or incorrect. If it is correct, mark A. If it is not correct, mark B. 1. Tanya Streeter’s world record in 2003 was the deepest she had ever dived. ........... 2. There were other people in the water with Tanya during her record-breaking dive. ........... 3. Tanya accepts that free-diving can be an extremely dangerous activity. ........... 4. Tanya’s training programme depends on the event she is preparing for. ........... 5. Most of Tanya’s training takes place in the water. ........... 6. Tanya is careful to limit the number of training dives she does in a month. ........... 7. Tanya spends more time helping environmental organisations than appearing in advertisements. ........... 8. Tanya’s interest in the natural world started at an early age. ........... 9. Tanya has found that being famous has its advantages. ........... 10. Because she started free-diving fairly late, Tanya feels her sports career may be short. ........... FREE-DIVING IN THE CARIBBEAN Tanya Streeter holds four world records in free-diving, the sport in which competitors reach extraordinary depths on only one breath of air. In 2003, Tanya Streeter made history when she became the first person to dive 120 metres into the ocean while holding her breath, and come back up to the top without help. She had been deeper a year before but on that occasion she swam back up using a balloon. This time, however, she held her breath for over three and a half minutes, which made her the only female in any sport to break the world record of a man. A team of fourteen safety divers at different depths watched the dive. Following reports of several serious accidents involving other divers, some people have complained that free- diving is too dangerous a sport, but Tanya doesn’t agree, insisting that safety is the most important thing, followed closely by training. Most free-divers concentrate on one or two types of event within the sport, but whatever Tanya is in training for, her practice timetable remains the same. Two thirds of the programme is spent doing land-based training at the gym, with the rest divided between the pool and the ocean. She uses an exercise bike to help improve thefitness of her heart. However, she doesn’t run, whether outdoors or on running machines, because she doesn’twant to injure her knees. Instead, she finds that fast walking is a very good way to build her fitness, when she starts doing practice dives, she generally travels away from home. She aims to do fourteen dives over a four-week period, with a rest day between each diving day. It is essential that she doesn’t get tired because that could ruin all the preparation. When Tanya is not preparing for an event, she makes frequent public appearances, mainly to advertise sports products. She has also supported environmental organisations, for example doing research projects or making films. Spending her childhood on the Caribbean island of Grand Cayman, she went swimming whenever she could, and long afternoons were spent exploring rock pools in order to watch the sea life. Tanya says that her life today is like living her childhood dreams. Because she is well-known in some countries, she thinks people are prepared to listen to her when she is talking about environmental issues. As for the future, Tanya, who is now in her thirties, says she plans to keep breaking her own world records. As she didn’t take up free-diving until she was twenty-five, Tanya is keen to stress that she doesn’t intend to retire from the sport for many years to come.

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